CN104365015A - Wiring material, solar cell module, and method for manufacturing solar cell module - Google Patents

Abstract

The present invention provides a wiring material (15, 16) comprising a conductor (20), a first layer (21) and a second layer (23). The conductor has a first surface (20a) and a second surface (20b) opposite to the first surface. The first layer is provided on the first surface of the conductor and contains a flux component and an antirust component. The second layer is provided on the second surface of the conductor and contains an adhesive (22).

Description

Wiring material, solar cell module, and method for manufacturing solar cell module

technical field

The present invention relates to a wiring material, a solar battery module using the wiring material and a manufacturing method of the solar battery module. Electrical junction box.

Background technique

In recent years, reducing environmental load has become a global issue, and solar power generation is expected to be a clean and renewable energy source. So far, the mainstream of solar cells has been to manufacture monocrystalline silicon and polycrystalline silicon crystals, and then slice them and use them as plate-shaped semiconductors. Bulk silicon solar cells. However, to manufacture bulk silicon solar cells, it takes a lot of energy and time to grow silicon crystals, and the manufacturing process is also complicated.

On the other hand, the so-called thin-film solar cell, in which a photoelectric conversion layer, that is, a semiconductor layer, is formed on a substrate such as glass or stainless steel, is considered to be the future solar cell due to factors such as thinness, light weight, low production cost, and easy large-scale expansion. mainstream. Thin-film solar cells include a type using amorphous silicon, a microcrystalline silicon film, or a type using them in tandem (tandem) type, etc., and a type using Cu (copper), In (indium), Ga (gallium), etc. ) and Se (selenium) as a representative of the compound semiconductor CIGS solar cells and the like.

These thin-film solar cells form solar cell strings (strings) by laminating semiconductor layers or metal electrode films on a large-area inexpensive substrate using a formation device such as a plasma CVD device or a sputtering device, and then patterning them with a laser. After separating the photoelectric conversion layers formed on the same substrate by laser patterning to form a plurality of solar cells, they are connected to each other.

A thin-film solar cell is constituted by, for example, a plurality of solar cells in which a transparent electrode film made of a transparent conductive film, a photoelectric conversion layer, and a rear electrode film are laminated on a light-transmitting insulating substrate. Each solar battery cell has an elongated strip shape and has a length substantially equivalent to the entire width of the translucent insulating substrate. In addition, for example, in two solar battery cells adjacent to each other, the transparent electrode film of one solar battery cell is connected to the back electrode film of the other solar battery cell, so that a plurality of solar battery cells are connected in series to form a thin film solar cell. . Then, a surface electrode is arranged on the transparent electrode film of the solar battery unit at the end, and the surface electrode and the junction box are connected by a tab wire, so that the electricity generated by the plurality of solar battery units is collected in the junction box, and since then output to the outside.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2009-295744

Patent Document 2: Japanese Unexamined Patent Publication No. 2012-9753

Contents of the invention

With regard to such thin-film solar cells, it is desired to provide a wiring material that enables good connection between a solar cell and a terminal portion of a junction box, a solar cell module using the wiring material, and a method for manufacturing the solar cell module.

In order to solve the above-mentioned problems, a wiring material according to one embodiment of the present invention includes a conductor, a first layer, and a second layer. The conductor has a first surface and a second surface opposite to the first surface. The first layer is provided on the first surface of the conductor and contains a flux component and an antirust component. The second layer is provided on the second surface of the conductor and contains a binder.

In addition, a solar cell module according to an embodiment of the present invention includes: a solar cell having a surface electrode, a junction box for outputting electricity generated by the solar cell to the outside, and an arrangement for electrically connecting the surface electrode of the solar cell and the junction box. wire. The wiring material includes a conductor, a first layer and a second layer. The conductor has a first surface and a second surface opposite to the first surface. The first layer is provided on the first surface of the conductor and contains a flux component and an antirust component. The second layer is provided on the second surface of the conductor and contains a binder.

In addition, one embodiment of the present invention is a method of manufacturing a solar cell module, which comprises providing a first layer containing a flux component and an antirust component on a first surface of a conductor, and The first surface is the second surface on the opposite side, and a second layer containing an adhesive is provided to form a wiring material; and one end of the wiring material is connected to the surface of the solar cell through the second layer, and is connected to the surface of the solar cell through the first layer. Junction box connection for external output of electricity generated by solar cells.

According to one embodiment of the present invention, the wiring material can be soldered and connected to the junction box for outputting the electricity collected from the solar cell, for example, through the first layer. At this time, since the first layer containing the flux component and the anti-rust component is formed on the wiring material, the wettability of the solder is improved, and fast and reliable soldering can be performed. In addition, since the solar cell is sealed with a light-transmitting sealing material such as EVA, the wiring material is exposed to the atmosphere of acetic acid gas as the temperature of the solar cell module rises, and there is a concern that corrosion may occur. However, since the first layer of the wiring material also contains anti-rust components, corrosion can also be prevented.

Description of drawings

FIG. 1A is a perspective view showing a wiring and a thin-film solar cell to which one embodiment of the present invention is applied.

FIG. 1B is a plan view showing a wire and a thin-film solar cell to which an embodiment of the present invention is applied.

Fig. 2 is an exploded perspective view showing a solar cell module according to an embodiment of the present invention.

Fig. 3 is a cross-sectional view showing a wiring to which an embodiment of the present invention is applied.

Fig. 4 is a cross-sectional view showing an adhesive.

Fig. 5 is a cross-sectional view showing wiring using a conductive adhesive film as an adhesive.

Fig. 6 is a plan view showing a solar cell module to which wiring is attached, omitting a sealing material and a back sheet.

Fig. 7 is an exploded perspective view showing a substrate-type solar cell module to which an embodiment of the present invention is applied.

Fig. 8 is an exploded perspective view showing another solar cell module to which an embodiment of the present invention is applied.

Fig. 9 is a cross-sectional view showing a connection portion between a collector wire and a connection wire.

Fig. 10 is a cross-sectional view showing a connection portion between a collector wire and a connection wire.

FIG. 11 is an exploded perspective view showing an example of a thin-film solar cell of a reference example.

12A is a plan view showing an example of a thin-film solar cell of a reference example.

Fig. 12B is a cross-sectional view of an electrode terminal portion of the thin film solar cell shown in Fig. 12A.

Detailed ways

Hereinafter, a wiring material to which an embodiment of the present invention is applied, a solar cell module using the same, and a method of manufacturing the solar cell module will be described in detail with reference to the drawings. In addition, this invention is not limited only to the following embodiment, It goes without saying that various changes are possible in the range which does not deviate from the summary of this invention. In addition, drawings are schematic, and the ratio of each dimension etc. may differ from an actual thing. Specific dimensions and the like should be determined from the following description. In addition, it is a matter of course that there are parts where the relationship and ratio of mutual dimensions are different among the drawings.

[solar battery module]

As shown in FIG. 1A and FIG. 1B , in a thin-film solar cell 1 to which an embodiment of the present invention is applied, a plurality of solar cell units 2 are connected by contact wires to form a solar cell string. As shown in FIG. 2, a thin-film solar cell 1 having such a string structure is formed on a glass substrate used as a surface cover 5, and a sheet 3 of sealing adhesive and a back sheet 4 (back sheet) are laminated on the back side. , and are laminated together. Thereafter, after suitably installing a metal frame 7 of aluminum or the like around it, a junction box 8 for outputting electricity collected from the thin film solar cell 1 is disposed on the back sheet 4 to form a solar cell module 6 .

As the sealing adhesive, for example, a light-transmitting sealing material such as ethylene-vinyl acetate copolymer resin (EVA: Ethylene Vinyl Acetate Copolymer) can be used. In addition, as the back sheet 4 , a laminate in which glass or aluminum foil is interposed between resin films, or the like can be used. In addition, in addition to forming the thin-film solar cell 1 on the glass substrate used as the surface cover 5, the solar cell module 6 can also be provided with the surface cover 5 and the thin-film solar cell 1 separately, and can be used between the surface cover 5 and the back plate 4. The sheets 3 of the sealing adhesive disposed on the front and back sides of the thin-film solar cell 1 are laminated and sealed. In this case, as the surface cover 5, for example, a translucent material such as glass or translucent plastic can be used.

[solar battery unit]

The thin-film solar cell 1 is formed by sequentially laminating a transparent electrode film composed of a transparent conductive film, a photoelectric conversion layer, and a back electrode film (not shown) on a light-transmitting insulating substrate 10 to transmit light from the light-transmitting insulating substrate 10. 10 side-injected super strate solar cells. In addition, thin-film solar cells also include substrate-type solar cells formed in this order from a base material, a back electrode, a photoelectric conversion layer, and a transparent electrode. Although the cladding-type thin-film solar cell 1 will be described below as an example, the present technology can also be applied to a substrate-type thin-film solar cell as described below.

As the translucent insulating substrate 10, heat-resistant resin such as glass or polyimide can be used. In addition, as described above, the thin-film solar cell 1 may also use the light-transmitting insulating substrate 10 and the surface cover 5 .

As a transparent electrode film, _SnO2 , ZnO, ITO etc. can be used, for example. As the photoelectric conversion layer, silicon-based photoelectric conversion films such as amorphous silicon, microcrystalline silicon, or polycrystalline silicon, or compound-based photoelectric conversion films such as CdTe, CuInSe ₂ , and Cu(In,Ga)Se ₂ , can be used.

The back electrode film has, for example, a laminated structure of a transparent conductive film and a metal film. _SnO2 , ZnO, ITO, etc. can be used for a transparent conductive film. As the metal film, silver, aluminum, or the like can be used.

In the thin-film solar cell 1 thus constituted, as shown in FIG. 1A , a plurality of rectangular solar cells 2 having a length substantially covering the entire width of the translucent insulating substrate 10 are formed. Each solar battery cell 2 is separated by an electrode dividing line, and among two adjacent solar battery cells, the transparent electrode film of one solar battery cell and the back electrode film of the other solar battery cell are connected to each other by a contact line. In this manner, a solar battery string in which a plurality of solar battery cells 2 are connected in series is formed.

Then, on the transparent electrode film of the solar battery cell 2 at one end of the solar battery string, a linear P-type electrode terminal portion 11 approximately as long as the solar battery cell 2 is provided. On the back electrode film of the solar battery cell 2 at the other end of the solar battery string, a linear N-type electrode terminal portion 12 approximately as long as the solar battery cell 2 is provided. In the thin-film solar cell 1 , these P-type electrode terminal portions 11 and N-type electrode terminal portions 12 serve as electrode extraction portions, and power is supplied to the junction box 8 through the positive electrode connection 15 and the negative electrode connection 16 .

[wiring (wiring material)]

As shown in Fig. 3, the wiring 15 for the positive electrode and the wiring 16 for the negative electrode include: a conductor 20, which is provided on one side 20a (the first surface) of the conductor 20 and is formed by mixing flux and a liquid with antirust function. The first layer 21 and the second layer 23 provided on the other surface 20 b (second surface) of the conductor 20 and composed of an adhesive 22 . The second layer 23 is used to connect the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 formed on the thin-film solar cell 1 with the respective conductors 20 of the positive electrode connection 15 and the negative electrode connection 16 .

The positive electrode wire 15 and the negative electrode wire 16 are connected to the junction box 8 through the first layer 21 by welding. The junction box 8 is used to output electricity collected from the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 to the outside.

The conductor 20 is a flat wire with a width of 1 mm to 3 mm that is substantially the same width as the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12. It is formed by rolling thin metal wires such as copper and aluminum into flat plates. On one side (S surface) 20a of the conductor 20, the first layer 21 composed of a liquid mixed with flux and antirust ink is formed over the entire surface, and on the other surface (M surface) 20b, the first layer 21 is formed over the entire surface. The second layer 23 composed of the adhesive 22 is formed.

[Tier 1]

The first layer 21 is formed by mixing a flux with a liquid having an antirust function, and coating the entire surface on one surface 20 a of the conductor 20 . That is, the first layer has a flux component and an antirust component. As the flux, for example, a flux for lead-free solder can be used. As the liquid having an antirust function, for example, antirust inks such as black ink doped with pigment-based carbon black or fluororesin-based inks can be used.

Such first layer 21 is formed to a predetermined thickness by applying a liquid mixed with flux and antirust ink to one surface 20a of conductor 20 with a wire bar or the like, and then evaporating the solvent in an oven.

The positive electrode wire 15 and the negative electrode wire 16 are soldered and connected to connection terminals of the junction box 8 for outputting electricity collected from the thin film solar cell 1 through the first layer 21 . At this time, since the first layer 21 contains a flux component, the wettability of the solder is improved, and soldering can be performed quickly and reliably. In addition, since the thin-film solar cell 1 is sealed by a translucent sealing material such as EVA, an acetic acid gas atmosphere is formed as the temperature of the solar cell module 6 rises, and there is a possibility that the wiring may be corroded. However, since the first layer 21 also contains an antirust component, corrosion can also be prevented.

＜Mix ratio＞

In addition, the ratio of the solid content of the flux and the anti-rust ink is preferably (flux): (anti-rust ink) = 1:3 ~ 3:1, more preferably (flux): (rust-proof ink) = 1:1～2:1 or (flux):(anti-rust ink)=1:1～1:2. As long as it contains flux components and anti-rust components, materials other than flux and anti-rust inks can also be used, as long as the mixing ratio of the solid content of the flux components and the anti-rust components is (flux components): (rust preventive components) ＝1:3～3:1 is enough.

Compared to the range of (flux):(rust preventive ink) = 1:3 to 3:1, if the solid content of the flux is large and the solid content of the rust preventive ink is small, the corrosion resistance will deteriorate. In addition, especially in a substrate-type thin-film solar cell, the positive-electrode lead 15 and the negative-electrode lead 16 are connected to the light-receiving surface side, and the appearance may be damaged. This is because if the solid content of the antirust ink is small, the black will become lighter. For example, in CIS-based or CIGS-based thin-film solar cells, the copper color of the conductor 20 will appear on the black background. In addition, compared with the above range, if the solid content of the flux is small and the solid content of the antirust ink is large, the wettability of the solder will deteriorate, and the connection terminal of the junction box 8 cannot be soldered quickly and reliably. , will also lead to an increase in connection resistance.

On the other hand, if the respective solid content ratios of the flux and the antirust ink are set within the above-mentioned ranges, deterioration of corrosion resistance and deterioration of appearance can be prevented. In addition, within this range, the black color of the rust-proof ink disposed on the positive electrode wiring 15 and the negative electrode wiring 16 on the light-receiving surface side can absorb ultraviolet rays and improve the weather resistance (light resistance) of the solar cell module. Furthermore, the wettability of solder can be improved, and soldering can be performed quickly and reliably.

[thickness of the first layer 21]

In addition, the thickness of the first layer 21 is preferably in the range of 1 μm to 10 μm, more preferably in the range of 1 μm to 8 μm, and most preferably in the range of 3 μm to 5 μm. As the thickness of the first layer 21 becomes thicker, the connection resistance tends to increase, and conversely, as the thickness becomes thinner, the corrosion resistance and appearance tend to deteriorate.

[Layer 2 (Binder 22)]

Next, the second layer 23 will be described. The adhesive 22 that constitutes the second layer 23 is used to connect the positive electrode wiring 15 and the negative electrode wiring 16 to the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 respectively, and conductive adhesive paste, conductive Adhesive film. The second layer 23 is formed by applying a conductive adhesive paste or sticking a conductive adhesive film on the other surface 20 b of the conductor 20 .

＜Conductive adhesive paste＞

As shown in FIG. 4 , adhesive 22 is formed by containing conductive particles 26 at a high density in thermosetting adhesive resin layer 25 . In addition, the minimum melt viscosity of the binder resin in the binder 22 is preferably 100 to 100,000 Pa·s from the viewpoint of press-fit properties. If the minimum melt viscosity of the adhesive 22 is too low, the flow of the resin will easily occur during the solidification process from the low-pressure connection, resulting in poor connection and leakage to the light-receiving surface of the unit, so that the light-receiving rate decreases. In addition, if the minimum melt viscosity is too high, defects are likely to occur at the time of film bonding, which will have a bad influence on connection reliability. In addition, the lowest melt viscosity can be measured by filling a sample in a quantitative rotational viscometer and raising the temperature at a predetermined temperature raising rate.

The conductive particles 26 used in the adhesive 22 are not particularly limited, and examples include metal particles such as nickel, gold, silver, and copper, particles formed by performing gold plating on resin particles, and particles formed by applying gold plating to resin particles. Particles formed by gold plating and the outermost layer of particles formed by insulating coating, etc.

In addition, the viscosity of the adhesive 22 around normal temperature is preferably 10 to 10000 kPa·s, more preferably 10 to 5000 kPa·s. Since the viscosity of the adhesive 22 is in the range of 10 to 10000 kPa·s, when the adhesive 22 is placed on the other side 20b of the conductor 20 and wound on the reel 27, the so-called Blocking (blocking) caused by seepage, maintain the specified adhesive (tack) force.

The composition of the adhesive resin layer 25 of the adhesive 22 is not particularly limited as long as the above-mentioned characteristics are not impaired, and it is more preferable to contain a film-forming resin, a liquid epoxy resin, a latent hardener, and a silane coupling agent.

The film-forming resin corresponds to a polymer resin having an average molecular weight of 10,000 or more, and the average molecular weight is preferably about 10,000 to 80,000 from the viewpoint of film-forming properties. As the film-forming resin, various resins such as epoxy resin, denatured epoxy resin, urethane resin, and phenoxy resin can be used, and among them, phenoxy resin is more suitable to be used in view of film-forming state and connection reliability. use.

The liquid epoxy resin is not particularly limited as long as it has fluidity at room temperature, and any commercially available epoxy resin can be used. Specifically, as such epoxy resins, naphthalene-type epoxy resins, biphenyl-type epoxy resins, phenol novolak-type epoxy resins, bisphenol-type epoxy resins, stilbene-type epoxy resins, three Phenol methane type epoxy resin, phenol arane type epoxy resin, naphthol type epoxy resin, dicyclopentadiene type epoxy resin and triphenylmethane type epoxy resin, etc. These epoxy resins may be used alone or in combination of two or more. In addition, it can also be used in combination with other organic resins such as acrylic resins as appropriate.

As the latent curing agent, various curing agents such as heat curing type and UV curing type can be used. Latent hardeners are usually nonreactive and are activated by some trigger to begin to react.

Triggers include heat, light, and pressure, which can be selected according to the application. Among them, in the present embodiment, it is suitable to use a heat-curable latent curing agent that is fully cured by heating and pressing the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 . When using a liquid epoxy resin, latent hardeners composed of imidazoles, amines, sulfonium salts, onium salts, and the like can be used.

As the silane coupling agent, epoxy-based, amino-based, mercapto-sulfide-based, ureido-based, and the like can be used. Among them, in the present embodiment, it is preferable to use an epoxy-based silane coupling agent. Therefore, the adhesiveness of the interface of an organic material and an inorganic material can be improved.

Moreover, it is preferable to contain an inorganic filler as another additive composition. By containing inorganic fillers, the fluidity of the resin layer during crimping can be adjusted, and the particle capture rate can be improved. As the inorganic filler, silica, talc, titanium oxide, calcium carbonate, magnesium oxide, and the like can be used, and the type of the inorganic filler is not particularly limited.

The adhesive 22 is formed by dissolving the conductive particles 26, a film-forming resin, a liquid epoxy resin, a latent curing agent, and a silane coupling agent in a solvent. As a solvent, toluene, ethyl acetate, etc., or a mixed solvent thereof can be used. The second layer 23 is formed by applying the dissolved conductive adhesive paste to the other surface 20b of the conductor 20, and then evaporating the solvent. As shown in FIG. 3 , the conductor 20 formed with the second layer 23 and the first layer 21 is wound on a reel 27 for storage, and in actual use, a predetermined length is pulled out from the reel 27 to be used as a positive electrode wire 15, The negative pole is used with connection 16.

Thereafter, the positive electrode wire 15 and the negative electrode wire 16 are temporarily pasted on the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 respectively. ) is heated and pressurized at a prescribed temperature and pressure. Therefore, the binder resin of the adhesive 22 is fluidized, and is filled between the conductor 20 of the P-type electrode terminal part 11 and the positive electrode connection 15, and the conductor 20 of the N-type electrode terminal part 12 and the negative electrode connection 16. between, and the conductive particles 26 are pinched between each wire (the wire 15 for the positive electrode, the wire 16 for the negative electrode) and each electrode terminal portion (the P-type electrode terminal portion 11, the N-type electrode terminal portion 12). Then, the binder resin hardens in this state. Therefore, the adhesive 22 can bond each wire to each electrode terminal portion, and can electrically connect each wire to each electrode terminal portion.

＜Conductive Adhesive Film＞

In addition, as the adhesive 22, instead of using a conductive adhesive paste, a conductive adhesive film may be used, and this may be pasted on the other surface 20b of the conductor 20. As shown in FIG. 5 , the conductive adhesive film 28 has an adhesive resin layer 25 laminated on a base film 29 and is formed into a belt like the conductor 20 . The base film 29 is not particularly limited, and PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methlpentene-1), PTFE (Polytetrafluoroethylene), and the like can be used.

When the conductive adhesive film 28 is used, the above-mentioned base film 29 is stuck on the adhesive resin layer 25 as a cover film. In this way, they are integrated by laminating the conductive adhesive film 28 on the other surface 20b of the conductor 20 in advance. Therefore, in actual use, the base film 29 is peeled off and the adhesive resin layer 25 of the conductive adhesive film 28 is pasted on the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 to realize the connection 15 for the positive electrode. , Temporary bonding of negative electrode wire 16 and each electrode terminal portion (P-type electrode terminal portion 11 , N-type electrode terminal portion 12 ). Thereafter, the adhesive resin layer 25 is cured by performing the same heat and pressure as in the case of the conductive adhesive paste.

In addition, when the second surface of the positive electrode wire 15 and the negative electrode wire 16 is a concavo-convex surface with many fine protrusions, the connection between the P-type electrode terminal portion 11 and the positive electrode wire 15, and the connection between the N-type electrode terminal portion 12 and the In the connection of the negative electrode lead 16 , an insulating adhesive such as an insulating adhesive film or an insulating adhesive paste may be used instead of the above-mentioned conductive adhesive paste or the conductive adhesive film 28 . At this time, many microscopic protrusions on the second surface are in contact with the surface electrodes of the solar cell to conduct electrical conduction, and the insulating adhesive is filled in regions where these microprotrusions are not in contact. The insulating adhesive film and the insulating adhesive paste have the same configuration as the conductive adhesive film and the electrically conductive adhesive paste except that the adhesive resin layer does not contain conductive particles.

[Manufacturing process of wiring]

Next, the manufacturing process of the lead wire 15 for positive electrodes and the lead wire 16 for negative electrodes is demonstrated. First, a metal foil such as copper foil or aluminum foil having a thickness of 50 μm to 300 μm is prepared to form the conductor 20 . Moreover, as a specific manufacturing method of a metal foil, the method of rolling a metal, the method of depositing a metal by electroplating, etc. can be illustrated. On one side (shiny side) of this metal foil, a liquid mixed with flux and antirust ink is applied with a wire bar or the like, and then dried to form the first layer 21 . Next, on the other side (mat side) of the metal foil, a conductive adhesive paste is applied with a wire bar or the like and then dried, or a conductive adhesive film 28 is laminated on them to integrate them. Thus, the second layer 23 made of the adhesive 22 is formed.

Next, by cutting this rolled metal foil, the first layer 21 is formed on one side 20a of the strip-shaped conductor 20, and the connection 15 for positive electrode and the second layer 23 are formed on the other side 20b. Wiring 16.

In addition, the connection 15 for the positive electrode and the connection 16 for the negative electrode can also be obtained by rolling thin metal wires such as copper and aluminum into a flat plate shape, or by cutting the rolled metal foil to obtain the strip-shaped conductor 20, and then form the first layer 21. Tier 2 23 to get.

As shown in FIG. 3 , the strip-shaped positive electrode wire 15 and negative electrode wire 16 are wound on a reel 27 for storage, pulled out from the reel 27 during use, cut into required lengths, and supplied to each electrode terminal. part (P-type electrode terminal part 11, N-type electrode terminal part 12) connection. At this time, because the first layer 21 made of flux and anti-rust ink is formed over the entire surface of one side 20a of the conductor 20 on the wire 15 for the positive electrode and the wire 16 for the negative electrode, and the other side of the conductor 20 is formed. The second layer 23 made of adhesive 22 is formed on the entire surface of one side 20b. Therefore, any part pulled out from the reel 27 can be used for connection to each electrode terminal part of the surface of the thin film solar cell 1. In addition, It can also be used for connection to the connection terminals of the junction box 8 .

[Wiring connection form 1]

As shown in Figure 6, such a positive pole wire 15 and a negative pole wire 16 have: connected to the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 through an adhesive 22, and connected to each electrode terminal portion (P-type electrode terminal portion 12). The electrode terminal part 11 , the N-type electrode terminal part 12 ) collects the current collector connection part 30 , and the connection connection part 31 extends to the junction box 8 and is connected to the connection terminal of the junction box 8 . The current collecting wire part 30 and the connection wire part 31 are connected by the bent part 32 .

The current collecting terminal portion 30 is a portion between one end of the positive electrode terminal 15 and the negative electrode terminal 16 and the bent portion 32 . The collector connection portion 30 is electrically and mechanically connected to the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 through the adhesive 22 of the second layer 23 formed on the other surface 20 b of the conductor 20 .

The connecting wire portion 31 is a portion between the other ends of the positive electrode wire 15 and the negative electrode wire 16 and the bent portion 32 . The connection wiring portion 31 extends along the surface of the thin-film solar cell 1 and passes through the sheet 3 of sealing adhesive and the back plate 4 ( FIG. 2 ), and reaches the connection terminal of the junction box 8 arranged on the back plate 4 . A part is soldered to the connection terminal of the junction box 8 through the first layer 21 formed on one surface 20 a of the conductor 20 .

Although the bent part 32 is to distinguish the boundary between the current collecting terminal part 30 and the connecting terminal part 31, the current collecting terminal part 30 and the connecting terminal part 31 are connected by the bending part 32, and the positive electrode wiring 15 and the negative electrode wiring 16 become absent. Seamless structure of joint parts. Therefore, it is possible to prevent an increase in resistance value due to the concentration of charges at the junction, a decrease in connection reliability at the junction, damage to the translucent insulating substrate 10 due to concentration of heat or stress at the junction, and the like.

In addition, although the connecting wire part 31 is extended and arranged on the surface of the thin film solar cell 1, because the one side 20a of the conductor 20 is covered by the insulating film 35, even if the connecting wire part 31 is in contact with the electrode film of the thin film solar cell 1, it can be reliably insulated. The membrane 35 prevents short circuits.

In addition, in the connecting wire portion 31, as the rust-proof ink constituting the first layer 21, non-conductive black ink containing carbon black after adjusting the pH is used, etc., so that the first layer 21 has insulation properties, so that it can be used without using. The insulating film 35 prevents a short circuit with the electrode film of the thin film solar cell 1 . Therefore, any part of the positive electrode wire 15 and the negative electrode wire 16 pulled out from the reel 27 can be used for each electrode terminal portion (P-type electrode terminal portion 11, N-type electrode terminal portion 12) on the surface of the thin film solar cell 1. ) connection, in addition, it can also be used for the connection of the connection terminal of the junction box 8.

When such positive electrode wiring 15 and negative electrode wiring 16 are used in the cladding type thin film solar cell 1, as shown in FIG. After 12, the connecting wire part 31 at the front end than the bent part 32 is properly arranged on the surface of the thin film solar cell 1 through the insulating film 35, and then passes through the sheet 3 of sealing adhesive such as EVA and the back sheet 4, and The connection terminals of the junction box 8 arranged on the back plate 4 are soldered.

In addition, when the wiring 15 for the positive electrode and the wiring 16 for the negative electrode are used in the substrate type thin-film solar cell 1, as shown in FIG. Afterwards, the connection wiring portion 31 at the front end than the bending portion 32 is arranged on the back side of the thin film solar cell 1, and then passes through the sheet 3 of sealing adhesive such as EVA and the back sheet 4, and is arranged on the back sheet 4. The connecting terminals of the junction box 8 are soldered.

The current collector wiring portion 30 of the positive electrode wiring 15 and the negative electrode wiring 16 is arranged on each electrode terminal portion (P-type electrode terminal portion 11, N-type electrode terminal portion 12), and the connection wiring portion 31 is arranged on the thin film. On the surface of the solar cell 1 , the front end thereof passes through the insertion hole formed in the sheet 3 of the sealing adhesive and the back sheet 4 . Thereafter, the positive electrode wire 15 and the negative electrode wire 16 are connected to each electrode terminal portion by a vacuum laminating machine, and the sheet 3 of the sealing adhesive between the surface cover 5 and the back plate 4 is used for one-time sealing. Laminated seal.

Next, after the metal frame 7 is set around the thin film solar cell 1, the front end of the connecting wire part 31 passing through the positive electrode wire 15 and the negative electrode wire 16 of the back plate 4 is connected to the wire provided on the back plate 4. The connection terminals of the box 8 are soldered. Thus, the solar cell module 6 is completed.

As described above, according to the solar cell module 6 of the present embodiment, since the first layer 21 of the positive electrode wire 15 and the negative electrode wire 16 contains flux, the wettability of the solder is improved, and fast and reliable soldering can be performed. In addition, since the thin-film solar cell 1 is sealed by a translucent sealing material such as EVA, the solar cell module 6 will be placed in an acetic acid gas environment as the temperature of the solar cell module 6 rises, so there is concern that the positive electrode wire 15 and the negative electrode wire 16 will be corroded. Since the first layer 21 also contains a liquid having an anti-rust function, it is also possible to prevent corrosion of the connecting wires 31 of the wires (the wire 15 for the positive electrode and the wire 16 for the negative electrode) arranged on the surface of the thin film solar cell 1 .

[reference example]

Here, the effect obtained by the solar cell module 6 of this embodiment will be described in more detail while comparing it with a reference example.

FIG. 11 shows a configuration example of thin-film solar cells constituting a solar cell string in a reference example. This thin-film solar cell 100 is composed of a plurality of solar cells 102 formed by laminating a transparent electrode film made of a transparent conductive film not shown, a photoelectric conversion layer, and a back electrode film on a translucent insulating substrate 101 . Each solar cell 102 has an elongated strip shape, and has a length substantially covering the entire width of the translucent insulating substrate 101 . In addition, in two adjacent solar cell units 102, the transparent electrode film of one solar cell unit is connected to the back electrode film of the other solar cell unit, so that a plurality of solar cell units 102 are connected in series to form a thin-film solar cell. 100.

On the transparent electrode film of the solar battery unit 102 at one end of the thin film solar battery 100, a P-type electrode terminal portion 103 approximately as long as the solar battery unit 102 is formed, and on the back surface of the solar battery unit 102 at the other end On the electrode film, an N-type electrode terminal portion 104 having a length substantially equal to that of the solar battery cell 102 is formed. These P-type electrode terminal portions 103 and N-type electrode terminal portions 104 serve as electrode extraction portions.

In the P-type electrode terminal portion 103, a positive electrode current collecting wire 105 made of copper foil is electrically and mechanically joined to the entire surface of the P-type electrode terminal portion 103 called a bus bar. Similarly, in the N-type electrode terminal portion 104 , a negative electrode current collecting lead 106 made of copper foil is electrically and mechanically joined to the entire surface of the N-type electrode terminal portion 104 . These joining means are generally performed by welding.

In addition, as shown in FIG. 12A , on the back side of the thin film solar cell 100, there are connected: a junction box 110 connected to the P-type electrode terminal portion 103 and the N-type electrode terminal portion 104 to transmit power to the outside, and a junction box for connecting the junction box. 110 and the junction box wiring 111 for the P-type electrode terminal portion 103 and the N-type electrode terminal portion 104 .

The junction box 110 is fixed to the center of the back surface of the thin film solar cell 100 with an adhesive, and a sealing resin such as EVA and a back sheet (not shown) are provided between the thin film solar cell 100 and the junction box 110 . Junction box wire 111 is made of elongated copper foil or aluminum foil similarly to positive electrode current collector wire 105 and negative electrode current collector wire 106 , and is arranged through the back surface of thin film solar cell 100 and insulating tape 112 .

One end of the connection box 111 passes through the sealing resin and the back plate, and is connected to the junction box 110 on the back plate by welding, and the other end is arranged on the P-type electrode terminal part 103 or the N-type electrode terminal through the insulating tape 112 Section 104 on.

As shown in FIG. 12B, the junction box connection 111 and the positive electrode current collection connection 105 are connected to the first and second positive electrode current collection connections 105a and 105b between the two sides sandwiching the insulating tape 112 and the junction box connection 111. On the side, the third positive electrode collector wire 105c extends between the 105a and 105b, and is connected across the insulating tape 112 and the junction box wire 111. In addition, the third positive electrode collector wire 105c is connected to the junction box wire 111 . These first and second positive electrode collector wires 105a and 105b are connected to the third positive electrode collector wire 105c (two places), and the third positive electrode collector wire 105c is connected to the junction box wire 111 (one place). ), is carried out using ultrasonic welding. The same applies to the connection between the negative electrode collector wire 106 and the junction box wire 111 .

However, in the thin film solar cell 100, various materials such as Al, Ag, and ZnO are used for the P-type electrode terminal portion 103 or the N-type electrode terminal portion 104 in order to adapt to the manufacturing method or configuration, etc. The difference caused a case where the connection strength with the positive electrode current collecting wire 105 or the negative electrode current collecting wire 106 could not be ensured due to welding. This may lead to an increase in connection resistance and a decrease in power generation efficiency.

In addition, when connecting the first and second positive electrode current collector wires 105a, 105b to the third positive electrode current collector wire 105c, or connecting the third positive electrode current collector wire 105c to the junction box wire 111, because the Since the thermal history in the high-temperature region of soldering increases locally, the translucent insulating substrate 101 made of glass or the like may be warped or damaged.

Then, a method of connecting the wires by a resin adhesive has been proposed instead of soldering. As such a resin binder, for example, one in which spherical conductive particles having an average particle diameter of several μm order are dispersed in a thermosetting binder resin composition and formed into a film is used. This method is to achieve the connection in the following way: a resin adhesive material that is thermoset at a temperature lower than the melting temperature of the solder is arranged between the wire and the P-type electrode terminal part and the N-type electrode terminal part, and the connection is made from the wire hot press on.

Among them, the use of an adhesive-attached wire in which a resin adhesive layer is preliminarily laminated on the surface can omit the step of arranging the resin adhesive, thereby effectively simplifying the manufacturing process.

However, when soldering a terminal portion of a junction box to a connection having a resin adhesive layer layered on its surface, it is necessary to remove the resin adhesive layer to expose the metal foil. Alternatively, it is necessary to laminate a resin adhesive material layer in advance on portions other than the connection portion to the terminal portion of the junction box to form an adhesive-attached connection. Thus, the manufacturing process of the solar cell module using the wire with an adhesive or the manufacturing process of the wire with an adhesive tends to be complicated.

In contrast, in the solar cell module 6 of the present embodiment, the current collecting terminal portion 30 and the connecting terminal portion 31 are connected by the bent portion 32, and the positive electrode terminal 15 and the negative electrode terminal 16 are seamless without joints. structure. In addition, the second layer 23 containing the binder 22 is connected to the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 of the thin-film solar cell 1 , and the first layer 21 is connected to the junction box. Therefore, the bonding process between the wires as described in the above reference example is not required, the manufacturing process can be simplified, and the following problems as described in the above reference example rarely occur: The increase in resistance value and the resulting reduction in power generation efficiency, reduction in connection reliability at the junction, damage to the translucent insulating substrate 10 due to heat and stress concentrated on the junction, and the like. In addition, the positive electrode wire 15 and the negative electrode wire 16 can be electrically connected to the junction box 8 by a simple method.

Furthermore, regarding the positive electrode wire 15 and the negative electrode wire 16 in the solar cell module 6 of the present embodiment, when insulation is provided to the first layer 21 of the connection wire portion 31, even if the insulating film 35 is not used, It is also possible to prevent a short circuit between the connecting wire portion 31 and the electrode film of the thin-film solar cell 1 . Therefore, any part of the positive electrode wire 15 and the negative electrode wire 16 pulled out from the reel 27 can be used for each electrode terminal portion (P-type electrode terminal portion 11, N-type electrode terminal portion 12) on the surface of the thin film solar cell 1. )Connection.

[Wiring connection form 2]

In addition, as shown in FIG. 8, the wiring 15 for positive electrodes and the wiring 16 for negative electrodes may be comprised by connecting plural wiring. That is, the positive electrode wire 15 and the negative electrode wire 16 can also be connected to the collector wire 36 connected to the P-type electrode terminal part 11 or the N-type electrode terminal part 12, and one end is connected to the collector wire 36 and the other end is connected to the junction box 8. The connecting wire 37 connected to the connecting terminal is constituted.

The collector wire 36 is electrically and mechanically connected to the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 through the adhesive 22 of the second layer 23 formed on the other surface 20 b of the conductor 20 .

In addition, the connection wires 37 extend on the surface of the thin-film solar cell 1 through the insulating film 35 , pass through the sealing adhesive and the back sheet 4 , and are connected to the connection terminals of the junction box 8 arranged on the back sheet 4 . The tip of the connection wire 37 is welded to the connection terminal of the junction box 8 through the first layer 21 formed on the one surface 20 a of the conductor 20 .

When such a positive electrode wire 15 and a negative electrode wire 16 are used in the cladding type thin film solar cell 1, as shown in FIG. , and one end thereof is disposed in the middle portion of each of the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 in the longitudinal direction. Collector wire 36 overlaps P-type electrode terminal portion 11 and N-type electrode terminal portion 12 , and is arranged to straddle one end portion of connection wire 37 . Such collector wires 36 and connection wires 37 are connected to each electrode terminal portion (P-type electrode terminal portion 11, N-type electrode terminal portion 12) by a vacuum laminating machine, and are connected between the surface cover 5 and the back plate 4. Disposable lamination sealing performed with 3 sheets of sealing adhesive. Thereafter, the other end of the connection wire 37 passes through the sheet 3 of sealing adhesive such as EVA and the back plate 4 , and is welded to the connection terminal of the junction box 8 arranged on the back plate 4 .

In addition, as shown in FIG. 10 , the connecting wire 37 may be arranged on the current collecting wire 36 with respect to the wire 15 for the positive electrode and the wire 16 for the negative electrode. That is, the second layer 23 of the collector wire 36 is arranged on the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12 . The second layer 23 of the connection wire 37 is disposed on the surface of the thin film solar cell 1 through the insulating film 35, and one end thereof is disposed on each length of the collector wire 36 provided on the P-type electrode terminal portion 11 and the N-type electrode terminal portion 12. The middle part of the edge direction. Such collector wires 36 and connection wires 37 are connected to each electrode terminal portion (P-type electrode terminal portion 11, N-type electrode terminal portion 12) by a vacuum laminating machine, and are connected between the surface cover 5 and the back plate 4. Disposable lamination sealing performed with 3 sheets of sealing adhesive. Thereafter, the other end of the connection wire 37 passes through the sheet 3 of sealing adhesive such as EVA and the back plate 4 , and is welded to the connection terminal of the junction box 8 arranged on the back plate 4 .

[Example]

Next, examples of the present invention will be described. In this embodiment, a plurality of wirings are prepared in which "the ratio of the solid content of the flux constituting the first layer 21 formed on one side 20a of the conductor 20 and the solid content of the antirust ink" is changed, and then the solderability, connection resistance, Appearance and corrosion resistance were investigated.

For the wiring of each example and comparative example, the ratio of the solid content of the antirust ink to the solid content of the flux was changed by changing the solid content of the antirust ink of the first layer 21 . In addition, the solid content of the first layer 21 including the flux solid content and the anti-corrosion ink solid content was fixed at about 24%, and a diluent solvent was appropriately blended therefor.

In Example 1, copper foil (manufactured by Furukawa Electric Co., Ltd.: GTS-MP) with a thickness of 35 μm was used as the conductor 20, and a mixed solution of flux and antirust ink was coated on one side 20a with a wire bar. Then, it was dried at 80° C. for 5 minutes to form the first layer 21 . In addition, a conductive adhesive paste is applied on the other surface 20 b of the conductor 20 to form the second layer 23 .

The thickness of the first layer 21 is 3 μm to 5 μm (4 μm thickness±1 μm). As a flux, mix ES-0307LS 3.00g manufactured by Senju Metal Co., Ltd. Among them, the flux solid content is 0.60g. As an antirust ink, 4.19 g of black ink containing pigment-based carbon black (manufactured by Dainichi Seika Co., Ltd.), 0.21 g of a crosslinking agent (manufactured by Dainichi Seika Co., Ltd.: SS hardener) and a diluting solvent (Dainichi Seika Co., Ltd.) were mixed. Chemical (stock) system: arumikku No. 18) 2.60g. The solid content of the anti-rust ink is 1.80g.

The solid content of the first layer 21, which combined the solid content of the flux and the solid content of the antirust ink, was 24%, and the mixing ratio of the solid content of the flux and the solid content of the antirust ink was (flux): ( rust ink) = 1:3.

The flux composition and the thickness of the first layer 21 in Example 2 are the same as those in Example 1. In addition, 2.79 g of black ink containing pigment-based carbon black (manufactured by Dainichi Seika Co., Ltd.), 0.14 g of a crosslinking agent (manufactured by Dainichi Seika Co., Ltd.: SS hardener) and a diluent solvent ( Dainichi Seika Co., Ltd.: arumikku No. 18) 1.57 g. The solid content of the anti-rust ink is 1.20g.

The solid content of the first layer 21, which combined the solid content of the flux and the solid content of the antirust ink, was 24%, and the mixing ratio of the solid content of the flux and the solid content of the antirust ink was (flux): ( Rust ink) = 1:2.

The flux composition and the thickness of the first layer 21 in Example 3 are the same as those in Example 1. In addition, as an antirust ink, 1.40 g of black ink (manufactured by Dainichi Seika Co., Ltd.) containing pigment-based carbon black, 0.07 g of a crosslinking agent (manufactured by Dainichi Seika Co., Ltd.: SS hardener) and a dilution solvent ( Dainichi Seika Co., Ltd.: arumikku No. 18) 0.53 g. The solid content of the anti-rust ink is 0.60g.

The solid content of the first layer 21, which combined the solid content of the flux and the solid content of the antirust ink, was 24%, and the mixing ratio of the solid content of the flux and the solid content of the antirust ink was (flux): ( rust ink) = 1:1.

The flux composition and the thickness of the first layer 21 in Example 4 are the same as those in Example 1. In addition, 0.70 g of black ink containing pigment-based carbon black (manufactured by Dainichi Seika Co., Ltd.) and 0.03 g of a cross-linking agent (manufactured by Dainichi Seika Co., Ltd.: SS hardener) were mixed as antirust ink, and no dilution was made. solvent. The solid content of the anti-rust ink is 0.30g.

The solid content of the first layer 21, which combined the solid content of the flux and the solid content of the antirust ink, was 24%, and the mixing ratio of the solid content of the flux and the solid content of the antirust ink was (flux): ( Rust ink) = 2:1.

The flux composition and the thickness of the first layer 21 in Example 5 are the same as those in Example 1. In addition, as the antirust ink, 0.47 g of black ink containing pigment-based carbon black (manufactured by Dainichi Seika Co., Ltd.) and 0.02 g of a crosslinking agent (manufactured by Dainichi Seika Co., Ltd.: SS hardener) were mixed, and no dilution was made. solvent. The solid content of the anti-rust ink is 0.20g.

The solid content of the first layer 21, which added up the solid content of the flux and the solid content of the anti-rust ink, was 23%, and the mixing ratio of the solid content of the flux and the solid content of the anti-rust ink was (flux): ( Rust ink) = 3:1.

Example 6 is the same as Example 3 except that the thickness of the first layer 21 is 1 μm to 3 μm.

Example 7 is the same as Example 3 except that the thickness of the first layer 21 is 5 μm to 8 μm.

Example 8 was the same as Example 3 except that an insulating adhesive film was used for the adhesive 22 of the second layer 23 .

In Comparative Example 1, the first layer 21 was formed by applying a liquid containing a flux component but not a rust preventive ink component. As a flux, mix ES-0307LS 10g manufactured by Senju Metal Co., Ltd. The flux solid content is 2.0g. Further, the contained solvent was volatilized by heating, and the solid content of the flux solid content, that is, the first layer 21 was adjusted to 24%. The mixing ratio of flux solids and anti-rust ink solids is (flux):(anti-rust ink)=1:0.

In Comparative Example 2, the first layer 21 was formed by applying a liquid containing antirust ink components but not containing flux components. As an antirust ink, 3.0 g of black ink containing pigment-based carbon black (manufactured by Dainichi Seika Co., Ltd.), 0.15 g of a crosslinking agent (manufactured by Dainichi Seika Co., Ltd.: SS hardener) and a diluting solvent (Dainichi Seika Co., Ltd.) Chemical (stock) system: arumikku No. 18) 2.01g. The solid content of the anti-rust ink is 1.24g. The anti-rust ink, that is, the solid content of the first layer 21 is 24%, and the mixing ratio of the solid content of the flux and the solid content of the anti-rust ink is (flux):(anti-rust ink)=0:1.

In Comparative Example 3, a wiring in which the first layer 21 was not formed on one surface of the conductor 20 was prepared.

Regarding the wiring of the above-mentioned examples and comparative examples, solderability, connection resistance, appearance, and corrosion resistance were examined. As for whether soldering is possible, use a soldering iron with a temperature of 400°C. If the soldering of the first layer 21 and the connection terminal of the junction box is completed within 10 seconds, it is considered good, and if the soldering is completed within 10 seconds or more than 15 seconds, it is considered acceptable. If the soldering is completed within 15 seconds If the welding cannot be completed within a period of time, it is regarded as defective.

Regarding the connection resistance, when energized at 2A, it is considered good if it is equal to the connection resistance value in welding of general copper foil, and it is acceptable if the connection resistance value in welding of general copper foil is less than 10mΩ. When the connection resistance value increased by 10 mΩ or more during welding, it was regarded as defective.

For visual inspection, when the wiring is visually observed after the formation of the first layer 21, if the copper color of the base cannot be confirmed, it is considered good, if the copper color of the base can be slightly confirmed, it is considered acceptable, and if the copper color of the base can be clearly confirmed, it is considered good. bad.

Regarding corrosion resistance, after sealing the EVA sheets for wiring in Examples and Comparative Examples, and performing a pressure cooker test (PCT: 85°C 85% 1000hr), when the first layer 21 is visually observed, if the first layer 21 cannot be confirmed If the discoloration is not confirmed, it is regarded as good, if significant discoloration cannot be confirmed, it is regarded as acceptable, and if significant discoloration is confirmed, it is regarded as defective.

[Table 1]

As shown in Table 1, in Examples 1 to 8, since the first layer 21 is formed by applying a liquid containing flux and antirust ink, the wettability of the solder is improved, and soldering can be performed quickly and reliably. Good results were also obtained for solderability and connection resistance. In addition, in Examples 1 to 8, even though they were sealed with EVA, an acetic acid gas atmosphere was formed as the temperature rose, and since the first layer 21 contained antirust ink, good results were obtained regarding corrosion resistance. Furthermore, in Examples 1 to 8, because the black ink containing pigment-based carbon black was used as the antirust ink, the color of the copper foil on the base did not appear, especially when it was attached to a substrate-type thin-film solar cell. Can maintain a good appearance.

On the other hand, in Comparative Example 1, since the flux component was contained, good results were obtained in terms of solderability and connection resistance, but since the anti-rust ink was not contained, the copper color of the base appeared clearly at the time of visual inspection, In addition, after the PCT test, discoloration of the wiring due to corrosion can be seen.

On the contrary, in Comparative Example 2, since the anti-rust ink was included, good results were obtained in appearance inspection and corrosion resistance, but because no flux component was contained, the soldering iron at 400°C was used for soldering within 15 seconds. Welding can be fully completed, so the connection resistance value also increased.

In Comparative Example 3, since the liquid containing the flux component and the antirust ink component was not applied, satisfactory results were not obtained in each item of solderability, connection resistance, appearance, and corrosion resistance.

In addition, according to the results of Example 2 and Example 3, it can be seen that the mixing ratio of the solid content of the flux and the solid content of the anti-rust ink is particularly good (flux): (rust-proof ink) = 1:1 ~ 1:2 .

In addition, comparing Example 6 with other examples, it can be seen that the thickness of the first layer 21 is preferably in the range of 1 μm to 10 μm, more preferably in the range of 1 μm to 8 μm, and most preferably in the range of 3 μm to 5 μm.

The present disclosure contains subject matter related to that disclosed in Japanese Priority Patent Application JP2012-158781 filed in the Japan Patent Office on Jul. 17, 2012, the entire content of which is hereby incorporated by reference.

It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alternatives may occur depending on design requirements and other factors as long as they are within the scope of the appended claims or their equivalents.

Claims (14)

1. A wiring material, wherein: A conductor having a first surface and a second surface opposite to the first surface; The first layer is provided on the first surface of the conductor and contains a flux component and an antirust component; and The second layer is provided on the second surface of the conductor and contains a binder. 2. The wiring material according to claim 1, wherein: The wiring material is configured to be connected to the surface electrode of the solar cell through the second layer, and connected to a junction box for outputting electricity generated by the solar cell to the outside through the first layer. 3. The wiring material according to claim 1, wherein, The compounding ratio of the flux component to the solid content of the antirust component is defined as (flux component):(rust preventive component)=1:3˜3:1. 4. The wiring material according to claim 1, wherein, The thickness of the first layer is 1 μm to 8 μm. 5. The wiring material according to claim 1, wherein, The wiring material is formed into a tape shape, and constitutes a package wound up on a reel. 6. A solar cell module, wherein: a solar cell having surface electrodes; a junction box for outputting the electricity generated by the solar cell to the outside; and a wiring material electrically connecting the surface electrodes of the solar cell and the junction box, The wiring material includes: A conductor having a first surface and a second surface opposite to the first surface; The first layer is provided on the first surface of the conductor and contains a flux component and an antirust component; and The second layer is provided on the second surface of the conductor and contains a binder. 7. The solar cell module according to claim 6, wherein, The wiring material is connected to the surface electrode of the solar cell through the second layer, and connected to the junction box through the first layer. 8. The solar cell module according to claim 7, wherein, The solar cell is a thin film solar cell, The first layer has insulating properties and is arranged on the surface of the solar cell. 9. The solar cell module according to claim 8, wherein, The wiring material has a seamless belt shape. 10. A method of manufacturing a solar cell module, comprising: A first layer containing a flux component and an antirust component is provided on a first surface of a conductor, and a second layer containing an adhesive is provided on a second surface of the conductor opposite to the first surface , so as to form a wiring material; The wiring material is connected to the surface of the solar cell through the second layer, and connected to a junction box for outputting electricity generated by the solar cell to the outside through the first layer. 11. The method of manufacturing a solar cell module according to claim 10, wherein, The compounding ratio of the flux component to the solid content of the antirust component is defined as (flux component):(rust preventive component)=1:3˜3:1. 12. The method of manufacturing a solar cell module according to claim 10, wherein, The thickness of the first layer is 1 μm to 8 μm. 13. The method of manufacturing a solar cell module according to claim 10, wherein, forming the wiring material into a strip shape, The tape-shaped wiring material is wound on a reel to form a package, pulling out the seamless wiring material from the package body, The surface of the solar cell and the junction box are connected by using the seamless wiring material. 14. The method of manufacturing a solar cell module according to claim 13, wherein, connecting one end of the wiring material to the surface electrode formed on the solar cell through the second layer, The other end of the wiring material is connected to the junction box through the first layer.